This study investigates the ability of EEG in identifying apnea/hypopnea events. A preliminary study was performed on 13 subjects (ages: 49.08+/-8.82) previously diagnosed with OSA. Power spectral analysis was performed and centered on apnea/hypopnea event terminations. The normalized power changes between the frequency bands delta, theta, alpha and sigma were calculated using the Welch Averaging Periodogram method between 10 s of EEG data before the event termination and 10 s of EEG data after event termination. A significant decrease in normalized Delta power (1-4 Hz) (p=1.34E-06) and a significant increase in normalized Theta (4-8 Hz) (p=0.0002), Alpha (8-12 Hz) (p=0.0001) and Sigma (12-16 Hz) (p=0.0007) powers were observed across the event terminations. The decrease in Delta is hypothesized as occurring due to an increase in inspiratory effort before events and the presence of an increased alpha/theta/sigma activity after the events indicates the occurrence of an arousal which led to the termination of the event.